Transparency is the cornerstone of a positive patient safety culture. Yet harmful errors are frequently not disclosed to patients, diminishing satisfaction and impairing healthcare quality. Important disclosure barriers include healthcare workers' lack of prior training as well as insufficient consideration of healthcare teams' role in disclosure. Following errors, teams of healthcare workers must reach consensus on difficult issues such as whether the event was an error, blame and responsibility, and whether to disclose the event. Our prior published experience suggests that simulation using standardized patients is an ideal modality for training healthcare workers to communicate more effectively with each other and with patients following errors. Therefore, we propose a pre/post simulation project with the following specific aims: 1) To determine whether team-based simulation training enhances healthcare workers' knowledge, attitudes, and skills in [unreadable] disclosing harmful errors to patients; 2) To determine whether team-based simulation training improves [unreadable] healthcare workers' knowledge, attitudes, and skills about team-communication; 3) To determine whether coaches demonstrate enhanced knowledge, attitudes, and skills compared to participants around team-based disclosure conversations. Participants represent diverse practice settings, and include 70 physicians and nurses, and 12 disclosure coaches from 4 University of Washington hospitals and a large health maintenance organization. The simulation involves teams responding to two cases of harmful errors by: 1) discussing the event, responsibility and blame, why the error happened, and how recurrences will be prevented; 2) planning whether and how to disclose the event to the patient; 3) disclosing the error to a standardized patient. A disclosure coach will help the teams discuss the error, plan the disclosure, and provide feedback. To enhance the clinical realism, a "standardized team member" (trained actor) will ensure teams confront key challenges such as discussing blame and resolving conflicts. The primary outcome is a pre/post analysis of the simulations' impact on healthcare workers' team communication and disclosure knowledge, attitudes, and skills as measured by a web-based assessment. Improving team communication and disclosure following harmful errors can enhance transparency and safety culture, increase patient satisfaction, and ultimately promote patient safety. [unreadable] [unreadable] [unreadable] [unreadable]